Avoid drawing the whole screen on each frame

This allows supporting 386DX "just about" (there will be flickering).

1 files changed, 9 insertions, 3 deletions

diff --git a/src/vga.h b/src/vga.h
index 06a69df..2441e24 100644
--- a/src/vga.h
+++ b/src/vga.h
@@ -21,14 +21,20 @@ void wait_frames(uint16_t frames);
 /* the palette is expected to be 8 bit per color, and will be converted to VGA's 6 bit per color */
 void set_palette(const uint8_t *palette);
 
+#define TARGET_SCREEN 0
+#define TARGET_BUFFER 1
+
+void blit_target(uint8_t t);
+
 void blit(const uint8_t *sprite, const Rect *dst);
 /* used for text: skip transparent, ignore 0, replace any other color by c */
 void blit_c(const uint8_t *sprite, const Rect *dst, uint8_t c);
 /* in src w is sprite width, h is sprite height */
 void blitrc(const uint8_t *sprite, const Rect *src, const Rect *dst);
 void blit_erase(uint8_t c);
-void blit_update();
 
-/* read from back buffer into memory */
-void read_buffer(uint8_t *dst, const Rect *src);
+/* copy from back buffer to screen */
+void blit_copy_all();
+void blit_copy(const Rect *dst);
+
 #endif /* _VGA_H */